Automatic die-press.



C. D..McDONALD.

AUTOMATIC DIE PRESS.

APPLlCATION FILED MAY 29. m1.

3 SHEETS-SHEET l.

f ATTORNEY Patented Apr. 23, 1918..

C. D. McDONALD.

AUTOMATIC DIE PRESS.

APPLICATION FILED MAY29. 1911.

Patented Apr. 23, 1918..

3 SHEETS-SHEET 2.

TGR,

1' N V EN C. D. McDONALD.

AUTOMATIC DIE PRESS.

APPLICATION FILED MAY 29. 1917.

lfififimmg Patented. Apr. 1918.

3 SHEETS-SHEET 3.

LES D. MODOND, 01B CHICAGO, ILLINOIS.

' .an'ronrarrc nrn-rnnss.

wearer.

Specification of Letters patent.

Patented Apr. ea, rat.

Application filed May 29, 1917. Serial Ito. 171,614.

To all whom it may concern Be. it known that I, CHARLES D. McDon- ALD, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois,.have invented certain new and useful Improvements in Automatic Die- Presses, of which the following is a specification.

The present invention relates to a means for connecting the drive shaft of a die-press to the slidable head which carries the movable die, and to the clutch mechanism for controlling the application of ower to the drive shaft, thus controlling t e operation of the press.

One of the objects of the invention is to provide a connection between the cross-head which carries the die and the power shaft, which connection will operate after the manner of a toggle, thus giving two work producing strokes to the cross-head for each revolution of the drive shaft and increasing the productive capacity of the press without increasing the speed of revolution of the power shaft beyond the normal speed of such shafts in ordinary machines of this character.

Another object of the invention is to so arrange the connection from the cross-head t0 the drive shaft as to have the pressure producedby the cutting action of the dies transmitted to the frame of the machine,

rather than to the drive shaft, thus making possible the employment of a relatively small drive shaft.

A further object of the invention is to provide a clutch mechanism which is so arranged as to efi'ect a disconnection between the drive shaft and the source of power for operating the press, which clutch mechanism after being set will effect such disconnection at the end of a half revolution of the drive shaft, thus bringing the mechanism to rest when the cross-head and die are in their full raised position.

The invention further consists in the features of construction and combination of parts hereinafter described and claimed.

In the drawings:

Figure 1 is a front View of one end of a press body equipped with the appliance of the present invention;

Fig. 2, a side elevation of the parts shown in Fig. 1, with the fly-wheel cut away;

Fig. 3, a detail section showing the Clutch pin in clutch g p t n;

]Fig. 4, a front view of the clutch mechanism;

Fig. 5, a detail partly in section and showing the clutch pin in retracted position;

Fig. 6, a section on line 6-6 of Fig. 4, looking in the direction of the arrows; Fig. 7, an elevation of one of-the clutch pin actuating arms; and

Figs. 8,9, 10 and 11, diagrammatic views showing the cross-head, die and toggle con nection from the drive shaft in the various positions assumed during one complete revolution of said shaft.

In the art to which the present invention relates, so far as I am aware, the cross-head which carries the die of an automatic diepress is operated by means of a crank shaft disposed above the cross-head, and with such method of operation, there is, of course, only one acting stroke of the die to each revolution of the crank shaft. It is of great importance in the operation of these die-presses that the largest possible number of acting strokes of the die be roduced, since this increases the capacity 0 the ma chine and hence its value to the user.

In the present invention, by means of a toggle. connection between the cross-head and drive shaft, I am enabled to get two acting strokes of the die during each revolution of the power shaft, thereby doubling the capacity of the press without rotating the drive shaft at any greater speed than it would be operated when a crank is used which would produce only one acting stroke of the die for each revolution of the drive the machine when desired, and it is also importantthat this clutch mechanism act to bring the press to rest when the cross-head and die are at their limit of up-stroke. ()tberwise, the mechanism would have to be moved by hand after the machine had been stopped, to place the die and cross-head at their upward limit of movement, in which position they would be ready to again commence operation.

When the die is operated with the toggle movement of the present invention, it is brought to its limit of upward movement twice during each revolution of the drive shaft and hence the clutch mechanism must be 0 such a nature that it will act when this cross-head is a die member 17, which cooperates with a fixed die member (not shown) in producing the work for wh1ch the press is intended. The die 17 is held in position on the cross-head by a block 18, secured by bolts or other suitable locking means 19 to the body of the cross-head.

Pivoted to the cross-head 16, by means of a pin 20, is alink member 21, which in turn is connected to a link member 22 by means of a turnbuckle 23. This turnbuckle comprises oppositely extending, threaded stems 24 (see Fig. 1), one of which is entered into the link member 21 and the other into the link member 22, and the pitch of the threads on these stems 24 is in opposite directions with respect to one another. 4

The links 21 and 22 are held in firm engagement with the stems 24 by means of bolts 25, each of the links being split as at 26 to allow of their being secured to and loosened from the stems 24. It. is obvious that by rotating this turnbuckle 23, the distance between the links 21 and 22 can be adjusted, and thus the position of the cross-head and die carried thereby adjusted with respect to the fixed 40 di e. The link 22 is connected by a pin 26 to a link 27, which link 27, at its upper end, is ivotally connected by a pin 28 to a lug or boss 29 joined or afiixed to the frame 12. The pin 26 also extends through the forked end 30 of an arm 31. This arm 31 is connected by a pivot pin 32 to a crank arm 33, which in turn is joined to the main drive shaft 34.

The arm 31, which may be referred to as the toggle actuating link, is of such length .that when the point ofconnection between said arm and the crank arm 33 is in vertical alinement with the drive shaft 34, the said arm will extend outward a distance to bring the pin 26 into vertical alinement with the pin 28 of the link 27 and the pin 20 of the link 21, which arrangement will cause the toggle to straighten out twice during each revolution of the drive shaft, causing a double action of the press.

The links 21, 22 and 27, together with the arm 31 and crank arm 33, constitute a con- I nection between the drive shaft 34 and the 6B cross-head 16, which carries the die; and, as

extending from a movable. cross-head 16. Aifixed to the lower end of Lseaeei will be apparent from the drawings, this connection effects a toggle movement as re spects the links 21, 22 and 27. The links 21 and 22 move as a unit, and so far as the toggle action is concerned, there are only two links, namely, the link 27, and the links 21 and 22 moving as one.

Assume that the parts are in the position shown in Fig. 8, wherein the toggle is broken in the direction of the drive shaft 34 and the cross-head and die are at their limit of up-stroke, and assume that a clutchin engagement is effected with the drive sha t to start the machine running, the first quarter revolution of the drive shaft will move the parts from the position of Fig. 8 to the position of Fig. 9, wherein the cross-head and die are brought to their lowermost position and an active cutting stroke of the die has been completed.

In'the position of Fig. 9, it will be noted that the toggle is straightened out. The second quarter revolution of the drive shaft moves the parts from the position of Fig. 9 to the position of Fig. 10, wherein the crosshead and die are again brought to their uppermost position and the toggle broken in a direction away from the drive shaft.

The third quarter revolution of the drive shaft brings the parts from the position of Fig. 10 to the position of Fig. 11, wherein the die is again at its lowermost position and a second active cutting stroke has been completed; and the fourth quarter revolution of the drive shaft returns the parts to the position of Fig. 8.

It will thus be apparent that for each revolution of the drive shaft, we have two" acting strokes of the die, namely, when the toggle is moved to its straightened position as in Figs. 9 and 11, wherein the die becomes active in a cutting operation. It is obvious that the strain resulting from the cutting action of the movable die with respect to the fixed die will be upward and will be transmitted through the links 21, 22 and 27 to the pin 28, and hence onto the frame of the machine, and will not be transmitted to the drive shaft. This permits the use of a small sized drive shaft, which, because of the fact that it has to be made of a high grade of steel, results in a substantial saving in the cost of producing the machine. I

In machines employing the ordinary and well known crank shaft above the crosshead, the strain of the cutting operation is transmitted back directly onto this shaft, necessitating the employment of a large sized shaft to withstand such strains.

In the foregoing construction, it is there-- fore possible to get two cutting operations from the die without increasing the number of revolutions of the drive shaft beyond a speed which would, produce only one cutmence a' downward or acting movement,

whereby it will commence to operate in synchrony with the feed bar, ejector, and other parts of the press mechanism. Also, the stopping of the press with the die in upposition renders the mechanism of the press more available for the purpose of repairs, etc. I

As explained, owing to the factthat the cross-head and die are raised twice during each revolution of the drive shaft, the clutch must be of such nature as to act when thedrive shaft shall have reached the terminus of the half revolution, wherein the die and cross-head are brought. to their limit of up-- ward movement.

The power for driving the press is ap-.

plied to a power shaft 35, by any suitable means. Keyed, or otherwise attached, to this shaft is a fly-wheel 35, to which is secured a hub 36 which contains a notch or recess 37. The hub and fly-wheel are formed integral or connected together, so that they turn as a single part. The drive shaft .34 has keyed, or otherwise connected thereto, a collar 38 comprising an upper reduced portion 39 and a lower enlarged portion 40, which provides a shoulder 41 be tween the portions 39 and 40. Resting upon this shoulder 41 are arms 42 and 43, which comprise the clutch actuating arms. Each of these arms is formed with a tapered surface 44, as will be apparent from Figs. 3, 5 and 6.

Carried by the collar 38 is a pin 45 formed with a notch or recess 45 at one side thereof. The pin 45 is held normally downward by a spring 46, and is adapted to enter into the recess 34 in the hub 36, and when so entered forms a clutching engagement between the hub 36 and the collar 38. The collar 38, it is to be remembered, is allixed to the drive shaft 34, while the hub 36 is affixed to the fly-wheel and is driven by the power shaft 35. Therefore, with the parts in the position as in Fig. 3, a clutching engagement is eflected between the fly-wheel and the power shaft when the press is in operation.

Reference has been made to the arms 42 and 43, and the construction and arrangement of these. arms will be more apparent from Figs. 2 and 6. The arm 42 is formed with a sloping or. wed e surface 44, and said arm is pivoted to roc upon a pin 47. To

the lower end of this arm is connected a link 48, which is also connected to the lower end.

to a bell crank 52 pivoted upon the pin 53.

Connected to this bell crank 18 a rod 54 joined to one end of a lever 55 pivotally mounted upon a pin 56; and connectedto the lever 55 and to one side of the pin 56 is a link or bar 57, connected by a in 58 to a hand lever 59, which is pivote as at 60.

This hand lever is intended to swing back and forth within the limits of stop members 61, which are adjustable, so that the distance of throw of the hand lever can be varied.

Also connected to the lever 55, and at the opposite end thereof from the point of connection of the rod 54, is a rod 62, connected by means of a link 63 to a spreader 64 adapted to operate upon brake members 65, which embrace and act against the periphery of the collar 38. The brake members are pivoted to swing about a hinge connection 66, and the brake sections are drawn together by means of a spring 67 mounted upon a suitable tie rod 68. I

With the parts in the position as shown in Fig. 2, the press is at rest and the clutch pin is drawn out into the position of .Fi 5 and retracted from the recess 37, so that t e driving connection between the collar 38 and hub 36 is broken, and in this instance the arms 42 and 43 have been moved inward to engage with the wall of the recess 45 to retract the pin 45, as in Fig. 5. Also the rod 62 is in such position as to cause the brake spreader 64 to release the brakes, and the spring 67 has acted to move the brakes into operative position.

Assumin that it is desired to start the press, the and lever 59 is thrown downward until it contacts the upper stop 61. This moves the link 57 downward and swings the lever 55 about its pivot, so as to move the rod 54 downward, which actuates the bell crank 52 so as to swing its upper end outward and away from the center of the collar 38. The link 51 is moved in a similar manner and the arm 43 is moved outwardly about its pivot 49 and away from the hub 38, and during such movement is guided by the shoulder 41 of the collar.

The outward movement of the arm 43 moves the link connection 48 and swings the arm 42 about its pivot 47, so that the upper ments by the shoulder 41. Such movement withdraws the tapered end 44 of the arm, which is in engagement with the wall of the recess 45", and the spring 46 acts to move the pin inward. It is to be remembered that the y-wheel continues to revolve while the press is at rest, and hence when the recess 37 in the hub 36 comes into position to receive the pin, said pin is forced into the recess by the pressure of the spring 46, and a clutch connection with the fly-wheel is effected.

* The ends of the sloping surface of the arms 42 and 43 are located diametrically opposite one another with respect to the center of the collar 38, as will be seen fromoFig. 6,'so that oneof these arms will engage in the recess 45 of the pin 45, to retract the pin from the recess 37 when the drive shaft 34 has moved to the end of a half'revolution wherein the cross-head and die are at the end of their upward movement. The movement of the lever 55 to set-the clutch actuat ing arms will also move the rod 62 and turn the brake spreader, whereupon the spring 67 will act to pull the brake members 65 inward and efiect a braking action to arrest the movement of the collar 38 and drive shaft 34. I

It is thought that the method of operation so of the press is quite apparent from the foregoing description and that no details thereof need be given. It is, of course, contemplated that structural changes in the machine as described and shown may be made,

and it is not intended to limit the scope of the invention other than may be by the terms of the appended claims.

I claim: 1. In an automatic die-press, the combina- 40 tion of a press body, a cross-head slidable on said body, a die carried by the cross-head, a-

toggle link pivotally connected to said crosshead, a toggle link pivotally connected to the pressbody at a point in vertical alinement with the point of connection between the cross-head and its toggle link, a drive shaft,

a crank arm connected to the drive shaft, a toggle actuated link connected at one end to the crank arm and at its other end to the pivotal connection between the toggle links, said actuating link being of a length where by when its .point of connection with the crank is in vertical alinement with the drive I shaft, its point of connection with the toggle pivot will be in alinement with the point of connection between the cross-head and its toggle and the press body and its toggle, whereby said links are straightened to lower the cross-head and broken to raise the crosshead twice during each revolution of the drive shaft, clutch mechanism for controlling the application of power to the drive shaft, and means for actuating said clutch mechanism to sto the application of power to the drive shat when the toggles are in substantially as described.

one or the other of their broken positions,

2. In an automatic die-press, the combination of a press body, a cross-head slidable on said body, a die carried by the cross-head a toggle link pivotally connected to said cross-head, a toggle link pivotally connected to the press body at a point in vertical alinement with the point of connection between the cross-head and its toggle link, a drive shaft, a crank arm connected to the drive shaft, a tog le actuated link connected at one end to t e crank arm and at its other end to the pivotal connection between the toggle links, said actuating link being of a length whereby when its point of connection with the crank is in vertical alinement with the drive shaft, its point of connection with the toggle pivot Wlll be in alinement with the point of connection between the crosshead and its tog 1e and the press body and its toggle, where y said links are straightened to lower the cross-head and broken to raise the cross-head twice during each revolution of the drive shaft, clutch mechanism for controlling the application of power to the drive shaft, means for actuating said clutch mechanism to sto the applicatlon of power to the drive sha t when the toggles are in one or the other of their broken positions, and brake mechanism operated by said clutch actuating mechanism to assist said clutch mechanism in bringing the drive shaft completely to rest at the proper point, substantially as described.

3. In an automatic die-press, the combination of a press body, a cross-head slidable on said body, a die carried by the cross-head a toggle link pivotally connected to said cross-head, a toggle link pivotally connected to the press body at a point in vertical alinement with the point of connection between the cross-head and its toggle link, a drive shaft, a crank arm connected to the drive shaft, atoggle actuated link connected at one end to the crank arm and at its other end to the pivotal connection between the toggle links, said actuating link being of a length whereby when its point of connection with the crank is in vertical alinement with the drive shaft, its point of connection with the toggle pivot will be in alinement with the point of connection between the cross-head and its toggle and the press body and its toggle, whereby said links are straightened to lower the cross-head and broken to raise the cross-head twice during each revolution of the drive shaft, .a power shaft, a springpressed slidable pin for effecting a clutch connection between said drive and ower shafts, arms lying upon opposite si es of the drive shaft, means for simultaneously 'moving said arms in opposite directions to cause them move in unison in and out from h p p y f the d ive shaf a h end thereof, the other arm actuating link is in horizontal alinement with the crank shaft to bring the press to ,rest when the toggle is broken and the crosshead raised, substantially as described.

4. In an automatic die press, the combination of a press body, a cross-head slidable on said body, a die carried by the crosshead, a toggle link pivotally connected to said cross-head, a toggle link pivotally connected to the press body at a pointin vertical alinement with the point of connection between the cross-head and its toggle link, a drive shaft, a crank arm connected to the drive shaft, a toggle actuated link connected to one end of the crank arm and at its other endto the pivotal connection between the toggle links, said actuating link being of a length whereby when its point ofv connection with the crank is in vertical alinement with the drive shaft, its point of connection with the togglev pivot will be in alinement with the point of connection between the cross-head andits toggle and the press body and its toggle, whereby said links are straightened to lower the crosshead and broken to raise the cross-head twice during each revolution of the drive shaft, a power shaft, a spring-pressed slida-.

ble pin for effecting a clutch connection between said power and drive shafts, said pin having a notch in one side thereof, arms pivotally mounted upon each side of the drive shaft, one arm being pivoted at one elng pivoted intermediate its ends, a connecting link between said arms, whereb they simultaneously move in opposite irections to carry them in unison 1n and out with respect to the drive shaft, each one of said arms having a cam surface adapted to engage and move said pin to break the connection between the power and drive shafts, whereby said drive shaft is allowed a maximum movement of one-half revolution after the clutch is set, and each arm acting to move said pin when the connection between the crank arm and toggle actuating llnk is 1n horizontal alinement with the crank shaft to bring the press to rest when the toggle is broken and the cross-head raised, substantially as described.

5. In an automatic die-press, the combination ofa press body, a cross-head slidable on said body, a die carried by the cross-head, a toggle link pivotally connected to said cross-head, a toggle link pivotally connected to the press body at a point in vertical alinement with the point of contac tlon between the cross-head and its toggle link, adrive shaft, a crank arm connected to the drive shaft, a toggle actuated link connected at one end to the crank arm and at its other end to the pivotal connection between the toggle links, said actuating link being of a length whereby when its point of connection with the crank is in vertical alinement with the drive shaft, its point of connection with the toggle pivot w1ll be in alinement with the point of connection be tween the cross-head and its toggle and the press body and its toggle, whereby said links are straightened to lower the cross-headand broken to raise the cross-head twice during each revolution of the drive shaft, a power shaft, a spring-pressed slidable pin for effecting a clutch connection between said drive and power shafts, arms lying upon opposite sides of the drive shaft, means for simultaneously moving said arms in opposite directions to cause them to move in. unison.

in and out from the periphery of the drive shaft, each one of said-arms having a cam surfaceadapted to engage and move said pin to break the connection between the .power and drive shafts, whereby said drive shaft is allowed a maximum movement of one-half revolution after'the clutch is set, and each arm acting to move said pin when the connection between the crank arm and toggle actuating link is in horizontal alinement with the crank shaft to bring the press to rest when the toggle is broken and the cross-head raised, a series of links and levers for actuating said arms, and brake mechanism actuated by said links and levers to operate the brakes in harmony with the clutch and assist the drive shaft to rest at the stantially as described.

6. In an automatic die-press, the combination of a press body, a cross-head slidable on said body, a die carried by the cross-head, a toggle link pivotally connected to said cross-head, a toggle link pivotally connected to the press body at a point in vertical alinement with the point of connection between the cross-head and its toggle link, a drive shaft, a crank arm connected to the drive shaft, a toggle actuated link connected at one end to the crank arm and at its other end to the pivotal connection between the toggle links, said actuating link being of a length whereby when its point of connection with the crank is in vertical alinement with the drive shaft, its point of connection with the toggle pivot will be in alinement with the point of connection between the crosshead and'its toggle and the pressbody and its toggle, whereby said links are straightened to lower the cross-head and broken to raise the cross-head twice during each revolution of the drive shaft, a power shaft, a

proper point, subare spring-pressed slidable pin'for effecting a clutch connection between said drive and power shafts, arms lying u on opposite sides of the drive shaft, means or simultaneously movingsaid arms in opposite directions to cause them to move in unison in and out from the periphery of the drive shaft, each one of said arms having a cam surface adapted to engage and move said pin to break the connection between the power and drive shafts, whereby said drive shaft is allowed a maximum movement of one-half revolution after the clutch is set, and each arm acting to move said pin when the connection between the crank arm and toggle mai actuating link is in horizontal alinemeht with the crank shaft to bring the press to rest when the toggle is broken an the cross-head raised, a main clutch operating lever, an intermediate lever, a connection between the operating lever and intermediate lever, a connection between said intermediate lever and arms, brake mechanism, and a connection between the intermediate lever and brake mechanism, whereby the brakes are 0 erated in harmony with the clutch mechanism and assist the latter in bringing the drive shaft to a complete stop at the proper point substantially as described.

CHARLES D. MCDONALD. 

